Differential assemblies are typically configured to transmit an input drive torque from a pinion gear to an axle output shaft through a ring gear, associated bevel pinion gears and a differential housing, which are mounted within a driveline assembly, such as an axle or transmission housing. The bevel pinion gears mesh with corresponding output bevel gears attached to left and right output shafts that extend one on each side of the ring gear. The differential assembly compensates for speed differences between left and right wheels connected to the left and right output shafts. Differential assemblies are typically of three types, a locking, limited slip and an open type. The differential housing may be one or two pieces and are generally constructed of cast iron. Indeed, cast iron differential housings are commonly used due to its low cost of manufacture and high strength. However, cast iron differential housings adversely impact vehicle weight by contributing significantly to the weight of a vehicle's rotating inertia. While the use of lower weight materials such as aluminum would significantly reduce the differential weight, issues surrounding the use of such lightweight materials have other concerns. For example, issues surrounding the use of aluminum housings may include decreased wear resistance at a contact area with a side gear shim, strength and deflection issues over the full operating temperature range, as well as increased transmission of noise and vibration.
Manufacturers are constantly attempting to reduce vehicle weight to improve fuel and driveline efficiency, which is a continued topic with regulators and a driving force of component design in the automotive industry. Housing size and weight are generally determined by the vehicle engine size, operating conditions, strength of the housing and clearances needed for the rotating assembly configured within the housing. Thus, it is desirable to find individual components that may be constructed of resilient materials and designs to minimize weight while maintaining or improving strength and resiliency of the components. Therefore, there is a need in drivetrain design to provide a differential that benefits from the weight savings of partial or all-aluminum housings, while maintaining the strength and economy of the all cast iron housing.